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From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
        linux-fsdevel@vger.kernel.org
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        James Morris <jmorris@namei.org>,
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        linux-ext4@vger.kernel.org, linux-audit@redhat.com,
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        Christian Brauner <christian.brauner@ubuntu.com>,
        Christoph Hellwig <hch@lst.de>
Subject: [PATCH v2 21/39] af_unix: handle idmapped mounts
Date:   Sun, 15 Nov 2020 11:37:00 +0100
Message-Id: <20201115103718.298186-22-christian.brauner@ubuntu.com>
In-Reply-To: <20201115103718.298186-1-christian.brauner@ubuntu.com>
References: <20201115103718.298186-1-christian.brauner@ubuntu.com>
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When binding a non-abstract AF_UNIX socket it will gain a representation in the
filesystem. Enable the socket infrastructure to handle idmapped mounts by
passing down the user namespace of the mount the socket will be created
from. Non-idmapped mounts will not see any altered behavior.

Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
---
 net/unix/af_unix.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index b4987805e5e5..4be33240e9cc 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -996,7 +996,7 @@ static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
 	 */
 	err = security_path_mknod(&path, dentry, mode, 0);
 	if (!err) {
-		err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, mode, 0);
+		err = vfs_mknod(mnt_user_ns(path.mnt), d_inode(path.dentry), dentry, mode, 0);
 		if (!err) {
 			res->mnt = mntget(path.mnt);
 			res->dentry = dget(dentry);
-- 
2.29.2